CN114688026A - Multi-cylinder rotary compressor - Google Patents

Abstract

The invention provides a multi-cylinder rotary compressor, which at least comprises two liquid accumulators and two cylinder groups, wherein the two cylinder groups are sequentially arranged along the height direction of the compressor, the two liquid accumulators are a first liquid accumulator and a second liquid accumulator, and the two cylinder groups are a first cylinder group and a second cylinder group; only one cylinder in each cylinder group is communicated with the reservoir; refrigerant entering from the first liquid storage device is compressed in two stages in the first cylinder group and then is discharged into a shell of the compressor along a flow path in a first direction parallel to the axial direction of the compressor; the refrigerant entering from the second accumulator is compressed in two stages in the second cylinder group and then discharged into the shell of the compressor along a flow path in the second direction parallel to the axial direction of the compressor; the second direction is opposite to the first direction; the compressor is suitable for the use environment with larger suction and exhaust pressure, the pressure ratio of single-stage compression can be effectively reduced, and the reliability of the compressor is improved.

Description

Multi-cylinder rotary compressor

technical field

The invention relates to the technical field of compressors, in particular to a multi-cylinder rotary compressor.

Background technique

The current rotary compressors are all developing in the direction of large capacity. Due to the limitation of the structural size of the whole machine, the cylinder capacity of such a large-capacity rotary compressor cannot be further increased. Therefore, a multi-cylinder method is generally required.

However, many multi-cylinder rotary compressors use the form of single-stage compression. As the refrigerant of the compressor gradually adopts a new type of refrigerant, the suction and discharge pressure ratio is generally larger; for example, the CO ₂ refrigerant, the suction pressure is 3.4MPa, The exhaust pressure reaches 12MPa. In such a use environment with a large ratio of suction and discharge pressures, the pressure ratio of a single stage of the compressor during operation will be greatly improved, the performance will be reduced, the long-term operation reliability of the compressor will be deteriorated, and damage will easily occur.

SUMMARY OF THE INVENTION

In view of this, the present invention provides a multi-cylinder rotary compressor, which effectively reduces the pressure ratio of single-stage compression and the resultant gas force on the crankshaft, thereby improving the reliability of the compressor.

According to one aspect of the present invention, a multi-cylinder rotary compressor is provided, which at least includes two accumulators and two cylinder groups arranged in sequence along the height direction of the compressor, wherein the two accumulators are the first accumulator. and a second liquid reservoir, the two cylinder groups are a first cylinder group and a second cylinder group; only one cylinder in each cylinder group is connected to the liquid reservoir;

After the refrigerant entering from the first accumulator is compressed in two stages in the first cylinder group, it is discharged into the casing of the compressor along a flow path in a first direction parallel to the axial direction of the compressor;

After the refrigerant entering from the second accumulator is compressed in two stages in the second cylinder group, it is discharged into the casing of the compressor along a flow path in a second direction parallel to the axial direction of the compressor; the second direction Opposite to the first direction.

Optionally, each cylinder in the cylinder group is provided with a vane groove to accommodate vanes for sliding, and the vanes are used to cooperate with the piston to separate the inner cavity of the cylinder into a suction chamber and an exhaust chamber; The included angle between the axes of the vanes corresponding to the two cylinders in the cylinder group is 0°, and the axes of the vanes corresponding to the two cylinders that are located in the adjacent two cylinder groups and are arranged adjacently along the axial direction of the compressor are respectively 0°. The included angle is greater than 90°.

Optionally, the compressor further includes an upper cylinder head and a lower cylinder head, the first cylinder group includes a first cylinder and a second cylinder communicated with the first accumulator; After the first-stage compression is performed in the second cylinder, the refrigerant entering the compressor enters the first cylinder for second-stage compression, and the refrigerant after the second-stage compression is discharged through the upper cylinder head to form the first cylinder. direction of the flow path;

The second cylinder group includes a fourth cylinder and a third cylinder communicated with the second accumulator; after the refrigerant entering from the second accumulator is compressed in the third cylinder in one stage, Enter into the fourth cylinder for secondary compression; the refrigerant after secondary compression is discharged through the lower cylinder head to form a flow path in the second direction.

Optionally, the compressor further includes a crankshaft, and the crankshaft is axially provided with a plurality of eccentric parts corresponding to the cylinders in the cylinder group one-to-one, and two adjacent eccentric parts are 180° symmetrical.

Optionally, each cylinder in the cylinder group has an intake port for inhaling refrigerant, and the phase difference between the intake port of the second cylinder and the intake port of the third cylinder is 180°, so The phase difference between the intake port of the first cylinder and the intake port of the fourth cylinder is 180°, and the phase difference between the intake port of the first cylinder and the intake port of the second cylinder is 0° .

Optionally, the plane formed by the axis of the intake port of the first cylinder and the axis of the intake port of the third cylinder is perpendicular to the end face of the first cylinder, and the plane of the intake port of the second cylinder is vertical. The plane formed by the axis and the axis of the intake port of the fourth cylinder is perpendicular to the end face of the first cylinder.

Optionally, each cylinder in the cylinder group has a suction port for sucking in refrigerant and an exhaust port for discharging refrigerant, the suction port is communicated with the suction chamber, and the exhaust port is The port communicates with the exhaust cavity, the suction cavity of the first cylinder and the suction cavity of the fourth cylinder are point-symmetrical about the center point of the end face of the first cylinder, and the suction cavity of the second cylinder and the The suction chamber of the third cylinder is point-symmetrical with respect to the center point of the end face of the second cylinder.

Optionally, the volumes of the suction chambers of the first cylinder and the fourth cylinder are equal and the volumes of the exhaust chambers are the same, and the volumes of the suction chambers of the second cylinder and the third cylinder are the same and the volumes of the exhaust chambers are equal. equal.

The beneficial effects of the present invention compared with the prior art are:

On the one hand, the multi-cylinder rotary compressor provided by the present invention realizes two-stage compression by connecting two cylinders in a cylinder group to a liquid accumulator, which can effectively reduce the pressure ratio of single-stage compression, and is beneficial to improve the reliability of long-term operation of the compressor. sex.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description serve to explain the principles of the invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

Fig. 1 is a structural cross-sectional view of a two-cylinder rotary compressor in the prior art;

Fig. 2 is the structural representation of the upper cylinder in Fig. 1;

Fig. 3 is the structural representation of the lower cylinder in Fig. 1;

4 is a structural cross-sectional view of a multi-cylinder rotary compressor disclosed in an embodiment of the present invention;

Fig. 5 is a structural cross-sectional view of the crankshaft in Fig. 4;

Fig. 6 is the structural representation of the first cylinder in Fig. 4;

Fig. 7 is the structural representation of the second cylinder in Fig. 4;

Fig. 8 is the structural schematic diagram of the third cylinder in Fig. 4;

FIG. 9 is a schematic structural diagram of the fourth cylinder in FIG. 4 .

Detailed ways

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments, however, can be embodied in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided in order to give a thorough understanding of the embodiments of the present disclosure. However, one skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced without one or more of the specific details, or other methods, materials, devices, etc. may be employed. In other instances, well-known solutions have not been shown or described in detail to avoid obscuring aspects of the present disclosure. The same reference numerals in the drawings denote the same or similar structures, and thus their detailed descriptions will be omitted.

The terms "a", "an", "the", "said" and "at least one" are used to indicate the presence of one or more elements/components/etc; the terms "include", "have" and "have" Included is used to mean open ended and means that additional elements/components/etc may be present in addition to the listed elements/components/etc.

The rotary compressors in the prior art are mainly single-cylinder and double-cylinder. A single-cylinder rotary compressor has one cylinder, and the cylinder is arranged between the upper cylinder head and the lower cylinder head. The suction port of the cylinder is connected to the reservoir. FIG. 1 is a schematic structural diagram of a two-cylinder rotary compressor in the prior art. As shown in FIG. 1 , the two-cylinder compressor includes a casing 101 , an upper cylinder head 102 , an upper cylinder 103 , an intermediate plate 104 , a lower cylinder 105 , a lower cylinder head 106 and a crankshaft 107 , and the intermediate plate 104 is located between the upper cylinder 103 and the lower cylinder Between the cylinders 105 , the upper cylinder 103 and the lower cylinder 105 are both disposed between the upper cylinder head 102 and the lower cylinder head 106 .

FIG. 2 and FIG. 3 are schematic structural diagrams of the upper cylinder 103 and the lower cylinder 105 in FIG. 1 , respectively. As shown in FIG. 2 , the inner space of the upper cylinder 103 is divided into a first intake chamber 203 and a first exhaust chamber 204 by the first vane 201 and the first piston 202 . As shown in FIG. 3 , the inner space of the lower cylinder 105 is divided into a second intake chamber 303 and a second exhaust chamber 304 by the second vane 301 and the second piston 302 . The crankshaft 107 drives the first piston 202 and the second piston 302 to rotate respectively.

The upper cylinder 103 has a first intake port 205, the lower cylinder 105 has a second intake port 305, and the first intake port 205 and the second intake port 305 are located on the same side, that is, the axis of the first intake port 205 The included angle between the projection of the axis of the second intake port 305 on the end face of the upper cylinder 103 is 0°.

In one aspect, the compressor is a single stage compression. In the environment where the ratio of discharge pressure to suction pressure is required to be large, single-stage compression makes the pressure ratio inside the compressor increase significantly, which makes the reliability of the internal components of the compressor worse under long-term operation, and reduces the compression rate. The reliability of long-term operation of the machine.

On the other hand, when the center point of the first piston 202 inside the upper cylinder 103 rotates through the angle θ, the center point of the second piston 302 inside the lower cylinder 105 will rotate through an angle of (θ+180°), and at this moment the first suction The volumes of the air cavity 203 and the second suction cavity 303 are always inconsistent, and similarly, the volumes of the first exhaust cavity 204 and the second exhaust cavity 304 are also always inconsistent. Because for a compressor with the same structural design, if the number of cylinders is simply increased in order to increase the displacement of the compressor, such as a four-cylinder compressor designed with the above-mentioned two-cylinder rotary compressor structure, then the four-cylinder compressor The crankshaft force of the cylinder compressor will be twice as high as the crankshaft force of the two-cylinder rotary compressor described above. This will significantly increase the risk of crankshaft deformation, and the bending of the crankshaft will adversely affect the fitting clearance of various components of the compressor pump body, resulting in the inability to guarantee the reliability of the large-displacement compressor. The direction of the arrows in FIGS. 2 and 3 is the flow direction of the refrigerant gas inside the cylinder.

Therefore, the present invention discloses a multi-cylinder rotary compressor. The compressor includes at least two accumulators and at least two cylinder groups arranged in sequence along the height direction of the compressor. And the number of cylinder banks is an even number. Only one cylinder in each cylinder group communicates with the accumulator. The refrigerant entering from the above-mentioned accumulator is discharged from the top of the compressor after being compressed in two stages in the above-mentioned cylinder group.

Each of the aforementioned cylinder groups includes two cylinders. Each cylinder is provided with a vane slot to accommodate the vane for sliding. The above-mentioned vanes are used for cooperating with the piston to divide the inner cavity of the cylinder into a suction cavity and an exhaust cavity. The included angle between the axes of the vanes corresponding to the two cylinders in each of the above cylinder groups is 0°. The included angle between the axes of the vanes corresponding to the two cylinders located in the adjacent two cylinder groups and arranged adjacently in the axial direction of the compressor is greater than 90°. By making the corresponding blades of the cylinders of the same cylinder group overlap, the included angles of the corresponding blades of the adjacent cylinders of different cylinder groups are greater than 90°, that is, the air intake ports of the cylinders in the same cylinder group are located on the same side, and the air intake ports of the cylinders in different cylinder groups are located on the same side. On different sides, the gas on the crankshaft when the compressor is running is reduced, which is beneficial to reduce the wear of the crankshaft and improve the operation reliability of the compressor.

The above two accumulators are a first accumulator and a second accumulator. The above two cylinder groups are a first cylinder group and a second cylinder group. After the refrigerant entering from the first accumulator is compressed in two stages in the first cylinder group, it is discharged into the casing of the compressor along the flow path in the first direction parallel to the axial direction of the compressor, and generates a second flow to the compressor. force in one direction. After the refrigerant entering from the second accumulator is compressed in two stages in the second cylinder group, it is discharged into the casing of the compressor along the flow path in the second direction parallel to the axial direction of the compressor, generating a first force in two directions.

In this embodiment, the above-mentioned compressor further includes an upper cylinder head and a lower cylinder head. The first cylinder group includes a first cylinder and a second cylinder in communication with the first accumulator. After the refrigerant entering from the first accumulator is compressed in the second cylinder, it enters the first cylinder for secondary compression, and the refrigerant after the secondary compression is discharged through the upper cylinder head of the compressor. The flow path of the above-mentioned first direction is formed.

The second cylinder group includes a fourth cylinder and a third cylinder in communication with the second accumulator. The refrigerant entering from the second accumulator is subjected to primary compression in the third cylinder, and then enters the fourth cylinder for secondary compression. The secondary-compressed refrigerant is discharged through the lower cylinder head of the compressor to form the flow path in the second direction.

That is, the present application utilizes two cylinder groups to realize two-stage compression respectively, so that in a use environment with a relatively large pressure-to-exhaust ratio, the pressure ratio of each stage of compression is reduced, which is beneficial to improve the long-term operation reliability of the compressor.

On the other hand, in the present application, the above-mentioned second direction is opposite to the above-mentioned first direction, so that the impact force generated by the gas flow paths in the two directions during the operation of the compressor can be partially offset, reducing the impact force and facilitating the compression stability during machine operation.

Wherein, the first cylinder, the second cylinder, the third cylinder and the fourth cylinder are arranged in sequence along the axial direction of the compressor, that is, they are arranged in sequence along the axial direction of the crankshaft.

In the present application, the compressor further includes a crankshaft, and the crankshaft is axially provided with a plurality of eccentric portions corresponding to the cylinders in the cylinder group one-to-one, that is, the eccentric portions are arranged in a one-to-one correspondence with the cylinders, and are opposite to each other. The two adjacent eccentric parts are 180° symmetrical. A piston is sleeved on each eccentric part.

Because in the prior art, in a large-capacity rotary compressor composed of multiple cylinders, the crankshaft is subjected to a relatively large force. In particular, as the displacement of the compressor tends to become larger and larger, the gas force on the crankshaft will also gradually increase with the increase of the displacement. The risk of crankshaft bending and deformation also increases, and crankshaft bending will adversely affect the fitting clearance of various components of the compressor pump body, resulting in reduced compressor reliability and performance.

The technical solution of the present application is beneficial to make the force of the gas in two adjacent cylinders on the crankshaft achieve an equal and opposite effect, reduce the force on the crankshaft, and improve the operation reliability of the compressor.

In the present application, each cylinder in the cylinder group has a refrigerant flow portion for sucking and discharging refrigerant. The said refrigerant|coolant flow part has an intake port and an exhaust port. Among them, the suction port is used to inhale the refrigerant, and the exhaust port is used to discharge the refrigerant. The axis of the intake port and the axis of the exhaust port define a predetermined line on the end face of a cylinder. The refrigerant circulation portion has a direction vector passing through the predetermined line. Therefore, each cylinder has a corresponding above-mentioned direction vector. The direction vector corresponding to the first cylinder is in the same direction as the direction vector corresponding to the second cylinder. The direction vector corresponding to the third cylinder is in the same direction as the direction vector corresponding to the fourth cylinder. The included angle between the direction vector corresponding to the second cylinder and the direction vector corresponding to the third cylinder is greater than 90°.

The volumes of the intake chamber and the exhaust chamber in the first cylinder and the fourth cylinder are respectively equal. This makes the gas in the first cylinder and the gas in the fourth cylinder have equal and opposite forces on the crankshaft. Therefore, the resultant force of the forces acting on the crankshaft by the gas in the first cylinder and the fourth cylinder is zero. Similarly, the resultant force of the gas in the second and third cylinders on the crankshaft is also zero. Therefore, the resultant force of each cylinder grouping on the crankshaft is always zero, thereby improving the stress on the crankshaft and reducing the bending deformation of the crankshaft.

Since the direction vector corresponding to the first cylinder is in the same direction as the direction vector corresponding to the second cylinder, and the eccentric parts in the first cylinder and the second cylinder are 180° symmetrical, the gas in the first cylinder and the gas in the second cylinder are 180° symmetrical. The resulting gas torque is consistent with the prior art twin-cylinder compressor. Similarly, the combined torque of the gas in the third cylinder and the gas in the fourth cylinder is also consistent with the prior art twin-cylinder compressor. Similarly, the combined torque of the gas in the third cylinder and the gas in the fourth cylinder is also consistent with the prior art twin-cylinder compressor. And the combined moment of the gas in the first cylinder and the gas in the second cylinder in each cylinder group is equal in magnitude and in the same direction as the gas in the third cylinder and the gas in the fourth cylinder. This makes the torque fluctuation of the compressor provided by the present application consistent with that of the conventional two-cylinder compressor under the premise of increasing the displacement and the number of cylinders, which is relatively gentle, and ensures low operating noise of the compressor.

FIG. 4 is a schematic structural diagram of a compressor corresponding to an embodiment of the present invention. As shown in FIG. 4 , in this embodiment, the compressor includes a crankshaft 408 , a first accumulator 409 , a second accumulator 410 and four cylinders. The four cylinders are the first cylinder 401 , the second cylinder 402 , the third cylinder 403 and the fourth cylinder 404 which are arranged in sequence along the axial direction of the crankshaft 408 . The compressor also includes a casing 405 , an upper cylinder head 406 and a lower cylinder head 407 . The four cylinders are arranged between the upper cylinder head 406 and the lower cylinder head 407 . Each cylinder has a hollow annular body.

As shown in FIG. 5 , the crankshaft 408 is provided with four eccentric parts, which are a first eccentric part 501 , a second eccentric part 502 , a third eccentric part 503 and a fourth eccentric part which are sequentially arranged along the axial direction of the crankshaft 408 . 504. The two adjacent eccentric parts are arranged symmetrically at 180°. The first eccentric portion 501 is located in the first cylinder 401, the second eccentric portion 502 is located in the second cylinder 402, the third eccentric portion 503 is located in the third cylinder 403, and the fourth eccentric portion 504 is located in the above in the fourth cylinder 404 .

As shown in FIG. 6 , the first cylinder 401 has a first refrigerant circulation portion 601 and a first annular body 602, and is provided with a first vane groove to accommodate the first vane 603 to slide. The first refrigerant circulation portion 601 includes a first intake port 604 and a first exhaust port 605 . A first piston 606 is sleeved on the first eccentric portion 501 , and the first piston 606 cooperates with the first vane 603 to divide the inner space of the first cylinder 401 into a first suction chamber 607 which communicates with the first suction port 604 . and the first exhaust chamber 608 communicated with the above-mentioned first exhaust port 605 .

Similarly, as shown in FIG. 7 , the second cylinder 402 correspondingly has a second refrigerant circulation portion 701 , a second vane 702 , a second piston 703 , a second intake port 704 , a second exhaust port 705 , and a second intake port 705 . Air cavity 706 , second exhaust cavity 707 and second annular body 708 . As shown in FIG. 8 , the third cylinder 403 correspondingly has a third refrigerant flow portion 801 , a third vane 802 , a third piston 803 , a third intake port 804 , a third exhaust port 805 , and a third intake chamber 806 , a third exhaust chamber 807 and a third annular body 808 . As shown in FIG. 9 , the fourth cylinder 404 has a corresponding fourth refrigerant flow portion 901 , a fourth vane 902 , a fourth piston 903 , a fourth intake port 904 , a fourth exhaust port 905 , and a fourth intake chamber 906 , a fourth exhaust chamber 907 and a fourth annular body 908 .

The second suction port 704 communicates with the first accumulator 409 described above. The third suction port 804 communicates with the second accumulator 410 described above. The refrigerant entering from the first accumulator 409 undergoes primary compression in the second annular body 708 of the second cylinder 402, and then enters the first annular body 602 of the first cylinder 401 for secondary compression. The stage-compressed refrigerant is discharged through the upper cylinder head 406 of the compressor to form the flow path in the first direction.

The refrigerant entering from the second accumulator 410 undergoes primary compression in the third annular body 808 of the third cylinder 403 , and then enters the fourth annular body 908 of the fourth cylinder 404 for secondary compression. The secondary-compressed refrigerant is discharged through the lower cylinder head 407 of the compressor to form the flow path in the second direction.

The first suction chamber 607 and the fourth suction chamber 906 are point-symmetrical with respect to the center point of the end face of the first cylinder 401 , and the first exhaust chamber 608 and the fourth exhaust chamber 907 are point-symmetrical with respect to the center point of the end face of the first cylinder 401 . point symmetry. The second suction chamber 706 and the third suction chamber 806 are point-symmetrical with respect to the center point of the end face of the first cylinder 401 , and the second exhaust chamber 707 and the third exhaust chamber 807 are point-symmetrical with respect to the center point of the end face of the first cylinder 401 symmetry.

Referring to FIGS. 6 to 9 , on the end face of the cylinder, the axis of the first intake port 604 and the axis of the first exhaust port 605 are symmetrical with respect to the second preset line, and the first direction corresponding to the first refrigerant circulation portion 601 The vector passes through the second preset line above. The axis of the second intake port 704 and the axis of the second exhaust port 705 are symmetrical with respect to the third preset line, and the second refrigerant flow portion 701 correspondingly has a second direction vector passing through the third preset line. The axes of the third intake port 804 and the third exhaust port 805 are symmetrical with respect to the fourth preset line, and the third refrigerant circulation portion 801 corresponds to a third direction vector passing through the fourth preset line. The axes of the fourth intake port 904 and the fourth exhaust port 905 are symmetrical with respect to the fifth preset line, and the fourth refrigerant circulation portion 901 corresponds to a fourth direction vector passing through the fifth preset line. The direction of the arrows in FIGS. 6 to 9 is the flow direction of the refrigerant gas inside the cylinder. It should be noted that, in other embodiments, each intake port may not be symmetrical with the exhaust port with respect to a preset line.

In this embodiment, the directions of the first direction vector and the second direction vector are the same. The directions of the third direction vector and the fourth direction vector are the same. The second direction vector and the third direction vector have opposite directions. That is, the angle between the second direction vector and the third direction vector is greater than 90°.

The plane formed by the axis of the first intake port 604 and the axis of the third intake port 804 is perpendicular to the end surface of the first cylinder 401 . The plane formed by the axis of the second intake port 704 and the axis of the fourth intake port 904 is perpendicular to the end surface of the first cylinder 401 .

In another embodiment of the present application, the above-mentioned second preset line coincides with the center line of the first blade 603 . The above-mentioned third preset line coincides with the center line of the second blade 702 . The above-mentioned fourth preset line coincides with the center line of the third blade 802 . The above-mentioned fifth preset line coincides with the center line of the fourth blade 902 .

Referring to FIGS. 6 to 9 , in this embodiment, the phase difference between the first air inlet 604 and the second air inlet 704 is 0°. The phase difference between the third intake port 804 and the fourth intake port 904 is 0°. The second intake port 704 and the third intake port 804 have a phase difference of 180°. The first intake port 604 and the fourth intake port 904 have a phase difference of 180°. The included angle between the axis of the first vane 603 and the axis of the second vane 702 is 0°. The included angle between the axis of the third vane 802 and the axis of the fourth vane 902 is 0°. The included angle between the axis of the second vane 702 and the axis of the third vane 802 is greater than 90°. Exemplarily, in this embodiment, the included angle between the axis of the second vane 702 and the axis of the third vane 802 is 180°. However, this application is not limited to this.

Continuing to refer to FIGS. 6 to 9 , when the center point of the first piston 606 inside the first cylinder 401 rotates through the angle θ, the center point of the second piston 703 inside the second cylinder 402 will rotate through (θ+180° )horn. At the same time, the center point of the third piston 803 inside the third cylinder 403 will rotate through an angle of (θ+180°), and the center point of the fourth piston 903 inside the fourth cylinder 404 will rotate through an angle θ.

Since the first intake port 604 and the fourth intake port 904 have a phase difference of 180°, the first eccentric portion 501 and the fourth eccentric portion 504 are also arranged symmetrically at 180°, so that at any moment of rotation of the crankshaft 408, The volumes of the first suction chamber 607 and the fourth suction chamber 906 are equal, and the volumes of the first exhaust chamber 608 and the fourth exhaust chamber 907 are also equal. Therefore, the force of the gas in the first cylinder 401 and the gas in the fourth cylinder 404 on the crankshaft 408 is equal in magnitude and opposite in direction. Similarly, at any moment of rotation of the crankshaft 408, the volumes of the second intake chamber 706 and the third intake chamber 806 are equal, and the volumes of the second exhaust chamber 707 and the third exhaust chamber 807 are also equal. The force of the gas in the second cylinder 402 and the gas in the third cylinder 403 on the crankshaft 408 is also equal in magnitude and opposite in direction. In this way, the force acting on the crankshaft 408 by all the cylinders is always zero, effectively reducing the gas force on the crankshaft 408, reducing the bending degree of the crankshaft 408, and improving the operation reliability of the compressor.

On the other hand, since the phase difference between the first intake port 604 and the second intake port 704 is 0°, the first eccentric portion 501 and the second eccentric portion 502 are arranged symmetrically at 180°, so that the structure formed by the two cylinders It is equivalent to the structure of a conventional twin-cylinder compressor, so the resultant moment of the gas in the first cylinder 401 and the gas in the second cylinder 402 is consistent with the twin-cylinder compressor in the prior art. Similarly, the resultant torque of the gas in the third cylinder 403 and the gas in the fourth cylinder 404 is also consistent with the prior art twin-cylinder compressor. And the resultant moment of the gas in the first cylinder 401 and the gas in the second cylinder 402 is the same in magnitude and in the same direction as the resultant moment of the gas in the third cylinder 403 and the gas in the fourth cylinder 404 . This makes the torque fluctuation of the compressor provided by the present application consistent with the conventional two-cylinder compressor in the prior art shown in FIG. 1 under the premise that the number of cylinders is increased to achieve a large displacement, which is relatively smooth and ensures the operation of the compressor. Low noise.

The multi-cylinder rotary compressor designed by adopting the idea of the invention of the present application can ensure the resultant force on the crankshaft even though the displacement of the compressor is increased compared with the two-cylinder rotary compressor in the prior art shown in FIG. 1 . It is always zero, which is beneficial to ensure the reliability of compressor operation.

In another embodiment of the present application, the radial width of the second annular body 708 is equal to the radial width of the third annular body 808 , and the radial width of the first annular body 602 is equal to the radial width of the fourth annular body 908 . As for the radial width, the radial width of the second annular body 708 is larger than the radial width of the first annular body 602, which is beneficial to improve the stability of the compressor during operation. The above-mentioned radial direction is the diameter direction corresponding to each annular body respectively.

To sum up, the multi-cylinder rotary compressor of the present invention has at least the following advantages:

The multi-cylinder rotary compressor disclosed in this embodiment, on the one hand, realizes two-stage compression by connecting two cylinders in a cylinder group to a liquid accumulator, which can effectively reduce the pressure ratio of single-stage compression, and is conducive to improving the long-term operation of the compressor. Reliability; on the other hand, by making the corresponding blades of the cylinders in the same cylinder group overlap, the angle between the corresponding blades of adjacent cylinders in different cylinder groups is greater than 90°, that is, the air intake ports of the cylinders in the same cylinder group are located on the same side, and different cylinders The air intake ports of the cylinders in the group are located on different sides, which reduces the gas on the crankshaft when the compressor is running, which is beneficial to reduce the wear of the crankshaft and improve the operation reliability of the compressor.

In the description of the present invention, it should be understood that the terms "bottom", "portrait", "horizontal", "top", "bottom", "front", "rear", "vertical", "horizontal", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated structure or element must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limiting the invention. Furthermore, features delimited with "first", "second" may expressly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "plurality" means two or more, and "several" means one or more.

In the description of this specification, description with reference to the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", etc. refer to the specific embodiment described in connection with the embodiment or example. A feature, structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more of the embodiments or examples.

The above content is a further detailed description of the present invention in combination with specific preferred embodiments, and it cannot be considered that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field of the present invention, without departing from the concept of the present invention, some simple deductions or substitutions can be made, which should be regarded as belonging to the protection scope of the present invention.

Claims (8)

1. The multi-cylinder rotary compressor is characterized by at least comprising two liquid accumulators and two cylinder groups, wherein the two cylinder groups are sequentially arranged along the height direction of the compressor, the two liquid accumulators are a first liquid accumulator and a second liquid accumulator, and the two cylinder groups are a first cylinder group and a second cylinder group; only one cylinder in each cylinder group is communicated with the reservoir;

refrigerant entering from the first liquid storage device is compressed in two stages in the first cylinder group and then is discharged into a shell of the compressor along a flow path in a first direction parallel to the axial direction of the compressor;

the refrigerant entering from the second accumulator is compressed in two stages in the second cylinder group and then discharged into the shell of the compressor along a flow path in the second direction parallel to the axial direction of the compressor; the second direction is opposite to the first direction.

2. The multi-cylinder rotary compressor of claim 1, wherein each cylinder of the cylinder group is provided with vane grooves for receiving vanes to slide, the vanes being adapted to cooperate with the pistons to divide the cylinder internal cavity into a suction chamber and a discharge chamber; the included angle of the axes of the blades corresponding to the two cylinders in each cylinder group is 0 degree, and the included angle of the axes of the blades corresponding to the two cylinders which are respectively positioned in the two adjacent cylinder groups and adjacently arranged along the axial direction of the compressor is larger than 90 degrees.

3. The multi-cylinder rotary compressor of claim 2, wherein the compressor further comprises an upper cylinder head and a lower cylinder head, the first cylinder group comprising a first cylinder and a second cylinder in communication with the first accumulator; refrigerant entering from the first reservoir enters the first cylinder for secondary compression after being subjected to primary compression in the second cylinder, and the refrigerant after the secondary compression is discharged through the upper cylinder cover to form a flow path in the first direction;

the second cylinder group includes a fourth cylinder and a third cylinder in communication with the second reservoir; the refrigerant entering from the second reservoir enters the fourth cylinder for secondary compression after being subjected to primary compression in the third cylinder; and discharging the refrigerant after the second-stage compression through the lower cylinder cover to form a flow path in the second direction.

4. The multi-cylinder rotary compressor of claim 1, further comprising a crankshaft having a plurality of eccentric portions axially provided in one-to-one correspondence with the cylinders of the cylinder group, respectively, and adjacent eccentric portions are 180 ° symmetrical.

5. The multi-cylinder rotary compressor of claim 3, wherein each cylinder of the cylinder group has a suction port for sucking a refrigerant, the suction port of the second cylinder is 180 ° out of phase with the suction port of the third cylinder, the suction port of the first cylinder is 180 ° out of phase with the suction port of the fourth cylinder, and the suction port of the first cylinder and the suction port of the second cylinder are 0 ° out of phase.

6. The multi-cylinder rotary compressor of claim 5, wherein the axis of the suction port of the first cylinder and the axis of the suction port of the third cylinder form a plane perpendicular to the end surface of the first cylinder, and the axis of the suction port of the second cylinder and the axis of the suction port of the fourth cylinder form a plane perpendicular to the end surface of the first cylinder.

7. The multi-cylinder rotary compressor of claim 3, wherein each cylinder of the cylinder group has a suction port for sucking a refrigerant, which communicates with the suction chamber, and a discharge port for discharging the refrigerant, which communicates with the discharge chamber, the suction chamber of the first cylinder and the suction chamber of the fourth cylinder are point-symmetrical with respect to a center point of a first cylinder end surface, and the suction chamber of the second cylinder and the suction chamber of the third cylinder are point-symmetrical with respect to a center point of a second cylinder end surface.

8. The multi-cylinder rotary compressor of claim 7, wherein the first cylinder and the fourth cylinder have the same suction chamber volume and the same discharge chamber volume, and the second cylinder and the third cylinder have the same suction chamber volume and the same discharge chamber volume.

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